1. Field of the Invention
The invention relates to skimmers for ponds and the like. More particularly, the invention relates to a combined skimmer, filter, and aeration apparatus as well as methods for its use.
2. State of the Art
Backyard ponds are very popular in many parts of the country. Ponds may vary in size from only a few square feet of surface area to one or more acres. The larger ponds are usually naturally formed whereas the smaller ponds are typically man-made. Solid waste invariably accumulates on the surface of a pond. Leaves, weeds, and other organic matter are among the most common solid waste found on the surface of ponds. In cases where the pond contains nutrients, such as fertilizers which run off surrounding land into the pond, different kinds of organic growth can live on the surface of the pond. The most common kinds of organic growth are watermeal and duck weed. In the case of small ponds, floating waste is easily removed with a hand skimmer or strainer. The larger ponds are not so easily cleaned. Eventually, the wind will blow most of the floating waste to an edge of the pond where it can be collected with hand skimmers or strainers. But the volume of waste in a larger pond calls for an automated solution.
Electrically operated pond skimmers are well known. Typical of the known pond skimmers are those sold by PondSweep Manufacturing, Co., 1204 Deer Street, Yorkville, Ill. 60560 and described in U.S. Pat. No. 5,584,991. These skimmers generally consist of an enclosure having side walls defining an internal chamber, typically two to three feet deep, which is permanently installed in a hole adjacent to the pond. A water inlet is formed near the top of the chamber adjacent to the surface of the pond water. Filter media such as various nets, screens, and/or baskets, depending on the particular model, are placed beneath the water inlet. A pump or a pump chamber is disposed beneath the filter media. The pump pumps water out of the chamber thereby causing a void which is filled by water from the surface of the pond. Debris which is floating near the water inlet is entrained by the water into the chamber and is captured by the filter media. Over time, the skimmer fills with debris and must be emptied. This involves removing the top of the enclosure and reaching down into the below ground container to remove the debris and clean the filter media. One might consider this periodic cleaning a disadvantage. However, it is generally accepted that all existing pond skimmers require some sort of periodic cleaning.
Existing pond skimmers are fixed in position and admit water and debris through a floating weir door. The floating weir door will automatically adjust for some changes in the water level of the pond. However, most natural ponds exhibit changes in water level which are beyond the range of the floating weir door. When the water level moves beyond the range of the floating weir door, the skimmer is inoperable.
It is apparent that a pond skimmer will only skim debris which is close enough to the water inlet. Depending on the size of the pond, and the prevailing winds, some debris may never reach the water inlet of the skimmer. The only solution to this problem is to install additional skimmers around the pond perimeter or to provide some way of generating a water current flowing towards the skimmer. Most people prefer the second option and this is typically accomplished with an artificial waterfall, a fountain, or a deep water aerator. Waterfalls and fountains are desirable, because, in addition to their aeration function which is good for the ecology of the pond, they are aesthetically pleasing. Waterfalls work well in man-made ponds which are designed for a waterfall and skimmer cooperation but may be impractical in natural ponds, depending on their size and shape. If a waterfall is not used, some sort of aeration device is desirable.